Linear guides are used to guide devices along a predetermined linear pathway in a highly accurate and repeatable fashion. Typically, these linear guides will include a guide rail, a carriage that is driven along the guide rail and a device for driving the carriage along the guide rail. In some embodiments, a screw may be the device for driving the carriage along the guide rail.
In highly precise applications, there is very limited, if any, clearance between the guide rail and the carriage and the screws are designed to have very high straightness. However, tolerance stack up between the guide surfaces of the guide rail and carriage as well as the screw in addition to any flexure in the components or variations due to machining can cause binding within the linear guide, as well as high or variable running torque. This variation in forces within the linear guide can affect the positional control of the carriage along the guide rail.
The present invention relates to improvements over the current state of the art in linear guides.